Infrared binocular system with dual diopter adjustment

ABSTRACT

Binocular system, including method and apparatus, for viewing a scene. The system may comprise a left camera and a right camera that create left and right video signals from detected optical radiation. At least one of the cameras may include a sensor that is sensitive to infrared radiation. The system also may comprise a left display and a right display arranged to be viewed by a pair of eyes. The left and right displays may be configured to present respective left video images and right video images formed with visible light based respectively on the left and right video signals.

CROSS-REFERENCES TO PRIORITY APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/023,424, filed Feb. 8, 2011, which in turn is based upon and claimsthe benefit under 35 U.S.C. §119(e) of U.S. Provisional PatentApplication Ser. No. 61/406,059, filed Oct. 22, 2010, and U.S.Provisional Patent Application Ser. No. 61/433,370, filed Jan. 17, 2011.Each of these priority applications is incorporated herein by referencein its entirety for all purposes.

INTRODUCTION

Various optical devices are available for providing magnified views ofdistant objects or scenes. These devices may be distinguished by whetherthey are based on lenses, mirrors, or both, by whether they have oneeyepiece or two, by whether they are handheld or mounted, and so on.Common handheld devices include monoculars, bioculars, and binoculars.Monoculars have one imager and one eyepiece. A user who uses this devicemay see an altered (e.g., magnified) view of the scene in one eye and anunaided view of the scene in the other eye. Bioculars have one imagerand two eyepieces. Here, the user's two eyes see the sametwo-dimensional (2D) altered image of the scene, with no depth or reliefcues provided by binocular disparity. Binoculars have two imagers andtwo eyepieces. Unlike bioculars, binoculars can create two separateimage-altered views of the world from two horizontally separatedviewpoints. The difference between these viewpoints can result inbinocular disparity between the left eye and the right eye retinalimages, which may, for those with normal binocular vision, provide cuesfor stereoscopic depth perception of the scene or a three-dimensional(3D) image.

Most handheld optical devices are intended for daytime use. However,recently, devices have been developed for nighttime use. Such nightvision systems may be based on image intensification (lightamplification) or thermal (infrared (IR) radiation) imaging. Mostconsumer night vision products are light amplifying devices, becauselight amplification is less expensive than imaging IR radiation. Lightamplification technology is dependent on at least a small amount ofambient light, such as moonlight or starlight, reflected off objects toprovide an amplified image. Infrared radiation, in contrast to ambientlight, may be emitted by an object, rather than (or in addition to)reflected off of it. Infrared radiation is a type of electromagneticradiation having wavelengths longer than those of visible light butshorter than those of radio waves. Infrared radiation is emitted fromall objects as a function of their temperature (as in the phenomenon of“blackbody radiation”). Hotter, and therefore more energetic, objectsgive off more infrared radiation at higher frequency and shorterwavelength than do cooler objects, because higher frequencies andshorter wavelengths correspond to higher energies. Thus, objects such ashumans or animals may be visualized and distinguished using IR imaging,in some case even in total darkness where no ambient light is present.

Examples of optical devices are disclosed in U.S. Pat. No. 7,098,458 andU.S. Patent Application Publication No. 2001/0045978, the disclosures ofwhich are incorporated herein by reference in their entireties for allpurposes.

SUMMARY

The present disclosure is directed to a binocular system, includingmethod and apparatus, for viewing a scene. The system may comprise aleft camera and a right camera that create left and right video signalsfrom detected optical radiation. At least one of the cameras may includea sensor that is sensitive to infrared radiation. The system also maycomprise a left display and a right display arranged to be viewed by apair of eyes. The left and right displays may be configured to presentrespective left video images and right video images formed with visiblelight based respectively on the left and right video signals.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of selected aspects of an exemplary binocularsystem, in accordance with aspects of the present disclosure.

FIG. 2 is an isometric view of an exemplary infrared binocular system,in accordance with aspects of the present disclosure.

FIG. 3 is a sectional view of the infrared binocular system of FIG. 2,taken generally along line 3-3 in FIG. 2.

FIG. 4 is a fragmentary view of a distal portion of the infraredbinocular system of FIG. 2, with part of the system's casing removed toreveal aspects of an objective focusing mechanism.

FIG. 5 is a fragmentary view of selected aspects of a proximal portionof the infrared binocular system of FIG. 2.

FIG. 6 is a sectional view of selected aspects of a visualization unitof the infrared binocular system of FIG. 2, taken generally along line6-6 of FIG. 5.

FIG. 7 is a fragmentary view of selected aspects of a proximal portionof another exemplary infrared binocular system, in accordance withaspects of the present disclosure.

FIG. 8 is a schematic view of an exemplary binocular system includingseparate camera and visualization units, in accordance with aspects ofthe present disclosure.

FIG. 9 is a schematic view of an exemplary binocular systemincorporating at least one additional camera, in accordance with aspectsof the present disclosure.

FIG. 10 is a schematic view of another exemplary binocular systemincorporating at least one additional camera, in accordance with aspectsof the present disclosure.

FIG. 11 is a schematic view of an exemplary binocular system thatoptically combines displayed images with images formed by focusingincident light, in accordance with aspects of the present disclosure.

DEFINITIONS

Technical terms used in this disclosure have the meanings that arecommonly recognized by those skilled in the art. However, the followingterms may have additional meanings, as described below. The wavelengthranges identified in these meanings are exemplary, not limiting, and mayoverlap slightly, depending on source or context. The wavelength rangeslying between about 1 nm and about 1 mm, which include ultraviolet,visible, and infrared radiation, and which are bracketed by x-rayradiation and microwave radiation, may collectively be termed opticalradiation.

Ultraviolet Radiation.

Electromagnetic radiation invisible to the human eye and havingwavelengths from about 100 nm, just longer than x-ray radiation, toabout 400 nm, just shorter than violet light in the visible spectrum.Ultraviolet radiation includes (A) UV-C (from about 100 nm to about 280or 290 nm), (B) UV-B (from about 280 or 290 nm to about 315 or 320 nm),and (C) UV-A (from about 315 or 320 nm to about 400 nm).

Visible Light.

Electromagnetic radiation visible to the normal human eye and havingwavelengths from about 360 or 400 nanometers, just longer thanultraviolet radiation, to about 760 or 800 nanometers, just shorter thaninfrared radiation. Visible light typically may be imaged and detectedby the unaided human eye and includes violet (about 390-425 nm), indigo(about 425-445 nm), blue (about 445-500 nm), green (about 500-575 nm),yellow (about 575-585 nm), orange (about 585-620 nm), and red (about620-740 nm) light, among others.

Infrared (IR) Radiation.

Electromagnetic radiation invisible to the human eye and havingwavelengths from about 700 or 800 nanometers, just longer than red lightin the visible spectrum, to about 1 millimeter, just shorter thanmicrowave radiation. Infrared radiation includes (A) IR-A (from about700 nm to about 1,400 nm), (B) IR-B (from about 1,400 nm to about 3,000nm), and (C) IR-C (from about 3,000 nm to about 1 mm). IR radiation,particularly IR-C, may be caused or produced by heat and may be emittedby an object in proportion to its temperature and emissivity. Portionsof the infrared having wavelengths between about 3,000 and 5,000 nm(i.e., between about 3 and 5 μm) and between about 8,000 and 12,000 nm(i.e., between about 8 and 12 μm) may be especially useful in thermalimaging, because they correspond to minima in atmospheric absorption andthus are more easily detected (particularly at a distance). Theparticular interest in relatively shorter wavelength IR has led to thefollowing classifications: (A) near infrared (NIR) (from about 780 nm toabout 1,000 nm (1 μm)), (B) short-wave infrared (SWIR) (from about 1,000nm (1 μm) to about 3,000 nm (3 μm)), (C) mid-wave infrared (MWIR) (fromabout 3,000 nm (3 μm) to about 8,000 nm (8 μm), or about 3 μm to 5 μm),(D) long-wave infrared (LWIR) (from about 8,000 nm (8 μm) to about15,000 nm (15 μm) or about 8 μm to 12 μm), and (E) very long-waveinfrared (VLWIR) or far infrared (FIR) (from about 15,000 nm (15 μm) toabout 1 mm). Portions of the infrared, particularly portions in the faror thermal IR having wavelengths between about 0.1 and 1 mm, mayalternatively, or in addition, be termed millimeter-wave (MMV)wavelengths.

Camera.

An image sensor alone or in combination with input optics that transmitincident radiation to the sensor. A camera may be described according tothe wavelength band that is detected, as determined by a combination ofthe spectral sensitivity of the sensor and the spectral selectivity, ifany, of the input optics. Each camera may, for example, be a visiblelight camera that predominantly or exclusively detects visible light, anultraviolet camera that predominantly or exclusively detects ultravioletradiation, or an infrared camera that predominantly or exclusivelydetects infrared radiation. If an infrared camera, the camera may be ashort-wave infrared camera that predominantly or exclusively detectsSWIR, a mid-wave infrared camera that predominantly or exclusivelydetects MWIR, a long-wave infrared camera that predominantly orexclusively detects LWIR, or a combination thereof (e.g., an MWIR/LWIRcamera), among others.

DETAILED DESCRIPTION

The present disclosure is directed to a binocular system, includingmethod and apparatus, for viewing a scene. The system may comprise aleft camera and a right camera that create left and right video signalsfrom detected optical radiation received from about a same field of viewalong respective left and right optical axes that are parallel to andoffset from each other. At least one of the cameras may include a sensorthat is sensitive to infrared radiation. The system also may comprise aleft display and a right display arranged to be viewed by a pair of eyesand configured to present left and right video images formed withvisible light, based respectively on the left and right video signals.In some embodiments, the left camera and the right camera may detect, orbe configured to detect, respective wavelength bands (of opticalradiation) that are different from each other. In some embodiments, thedisplays also may be configured to present other information, such asalphanumeric characters and/or other symbols, with one of the displaysas both displays present video images, such that the other informationis only seen with one eye when the video images are viewed by a pair ofeyes.

The present disclosure relates to a binocular system that may use thehuman visual system (HVS) to compute depth perception. Specifically,aspects of the disclosure relate to an infrared binocular systemincluding two infrared cameras to create left and right video signals(or streams) that are communicated (with or without manipulation by acontroller) to separate visualization units, such as units includingminiature displays. The displays present left and right video imagesseparately to left and right eyes of a user based on the correspondingvideo signals. The HVS of the user may reconstruct the video images intoa real time 3D video with depth perception. The system may allowdistance to objects and object relative locations to be determined bythe observer in a passive manner, without the use of laser rangefinders.

The binocular system may present left and right video images to a userin real time, generally with no perceptible delay between creation ofvideo signals by the cameras and presentation of corresponding videoimages by the displays. Use of the human visual system to blend and/orcompare left and right video images generally can be performed much morerapidly than with an onboard computer. Accordingly, the system disclosedherein may rely on the user's brain to integrate and/or contrast, inreal time, left and right video images collected by correspondingcameras that detect different wavelengths of optical radiation.Integration of these video images by the user's visual system mayprovide depth cues for a scene, and comparison of the video images mayidentify objects/features of interest in the scene. For example, in somecases, regions of the scene that appear most similar at the differentwavelengths may be integrated more easily by the user's visual system toprovide context information and/or depth cues. In contrast,objects/features of interest in the scene that appear more distinct fromeach other at the different wavelengths may stand out because they aremore difficult for the visual system to integrate. Alternatively, theleft and right video images may be configured (e.g., by using an inversepolarity and/or different palettes for the two sets of video images)such that objects/features of interest are relatively more easilyintegrated by the user's human visual system than the rest of the scene.

Further aspects of binocular systems are disclosed in the followingsections, including (I) overview of an exemplary binocular system, (II)controller capabilities, and (III) examples.

I. OVERVIEW OF AN EXEMPLARY BINOCULAR SYSTEM

FIG. 1 is a schematic view of selected aspects of an exemplarymulti-channel imaging system or binocular system 20 for viewing a scene22 composed of distant objects 24. The binocular system may be describedas electronic binoculars that comprise at least two side-by-sidemonocular assemblies (or telescopes) 26, 28. Each monocular assembly maybe capable of detecting incident optical radiation, to create arepresentative video signal (i.e., image data representing a sequence ofdetected images). The video signal may (or may not) be manipulated,generally electronically, before being converted back into opticalradiation, to produce visible light images corresponding to the incidentoptical radiation. In contrast to strictly optical binoculars, input andoutput optical paths of the system do not need to connect to oneanother. Furthermore, in some cases, the input and output optical pathsmay be defined by respective, separate units that are movableindependently of one another and/or that are remote from one another.

Monocular assemblies 26, 28 may be supported and enclosed by a supportassembly 29 (also termed a frame, housing, or body), which may hold theassemblies on respective input optical axes 30, 32 that are parallel toand offset (i.e., spaced) from one another. Assemblies 26, 28 may bearranged to be used by a pair of eyes 34, 36 of a person at the sametime, with the eyes positioned on output optical axes 38, 40 forseparate viewing of left video images and right video images.

Exemplary functional and structural relationships among components ofsystem 20 are shown schematically in FIG. 1. Electrical and/or signalcommunication between components is represented schematically by curvedlines. Each site of communication may be via a wired or wirelessconnection. Mechanical connections are represented schematically bystraight lines, and, optionally, may be replaced or augmented byelectrical communication. Exemplary permitted motions of selected systemcomponents, to adjust the position of the selected components relativeto support assembly 29, are indicated by double-headed motion arrows andby phantom representations of the selected components. Exemplary lightrays entering, exiting, and traveling within the system are presentedschematically as dashed lines of uniform dash length. These exemplarylight rays are intended to draw attention to portions of the systeminvolved in detecting and displaying images and not to portray the exactpathways followed by the light (which will depend on particulars of theoptics).

Each monocular assembly 26, 28 may include (A) input optics 42 (such asan objective) for gathering, directing, filtering, and/or focusingradiation, such as infrared radiation, incident along one of inputoptical axes 30, 32, (B) a sensor 44 (also termed an image sensor) fordetecting images formed by the input optics on the sensor and convertingthe images into a representative video signal, (C) a display 46 forconverting the video signal into video images formed with visible light,and (D) output optics 48 (also termed an eyepiece) that a user mayutilize to see the video images. The monocular assembly and/or system 20also may include a controller 50 to manipulate the video signal beforeit is communicated to the display, and to control operation of, receiveinputs from, and/or otherwise communicate with components of themonocular assembly and/or binocular system, such as controllingpresentation of images by the displays based on the signals. Themonocular assembly, system 20, or a camera unit or presentation unitthereof (see Section III), further may include at least one power supply52 to power system components and at least one user interface 54 tocommunicate user inputs to controller 50, power supply 52, and/or othermechanisms of the system. Each sensor 44 and its associated input optics42 may be described as a camera or a collector (56 or 58).

Input optics 42 may be composed of one or more optical elements thattransmit incident radiation to sensor 44. An optical element is anystructure or device that collects, directs, and/or focuses opticalradiation and/or selectively blocks undesired radiation. An opticalelement may function by any suitable mechanism, such as refracting,reflecting, diffracting, and/or filtering, among others, opticalradiation. Exemplary optical elements include lenses, mirrors, gratings,prisms, filters, beam splitters, transmissive fibers (fiber optics), orthe like. The input optics may define an optical path traveled byincident radiation to the sensor. Also, the input optics may form anoptical window through which optical radiation is received by amonocular assembly and/or camera. In exemplary embodiments, the inputoptics may include a multispectral objective capable of gathering andfocusing radiation of various wavelengths, for example, multipleinfrared wavelengths (any combination of near-IR, SWIR, MWIR, and LWIR),infrared and visible wavelengths, ultraviolet and visible wavelengths,or ultraviolet, visible, and infrared wavelengths, among others.

The input optics may include one or more coatings (e.g., to reduce glareand/or reflections and/or for protection), at least one filter 55 (e.g.,to block undesired radiation), and/or the like. The coatings may includea hard coating, such as diamond or diamond-like carbon, on an exteriorsurface region of each objective lens to improve durability. The filtermay be a wavelength filter, an intensity filter, a polarizing filter, asafety filter to block light from a laser (such as a laser weapon), orthe like. Exemplary wavelength filters include a band-pass filter, ahigh or low cut-off filter, a notch filter, or any combination thereof,among others. The filter may block only part of a spectral range, suchas blocking only part of the spectral range of infrared radiation, onlypart of the LWIR range (an LWIR filter), only part of the MWIR range (anMWIR filter), only part of the SWIR range (an SWIR filter), only part ofthe visible range (a visible light filter), and so on. The filter may bedisposed or disposable on the optical path that incident radiationtravels to the sensor, and thus is interposed or interposable between anobserved scene and the sensor.

The filter may be integral to the system or may be attached removably,such as to an exterior and/or an objective end of a monocular assembly,to incorporate the filter into a camera. In some cases, the filter maybe connectable over an objective (i.e., between the objective and thescene) to enhance viewing. In other cases, the filter may be disposed(permanently or removably) in the optical path within the objective orbetween the objective and the sensor. Exemplary approaches forconnecting the filter include threaded engagement, snap-on, a frictionor interference fit, fasteners (such as screws or pins), or the like.The filter(s) may be easily removable or interchangeable to facilitateready reconfiguration of the system for different uses and/or users.

One or both cameras 56, 58 optionally may be equipped with a filter,such as a wavelength filter and/or a polarizing filter, among others. Ifboth cameras include a wavelength filter, the wavelength filters for thecameras may selectively block the same or different wavelength ranges ofoptical radiation. For example, the cameras may use respective filtersthat filter distinct types of optical radiation, such as an infraredfilter that blocks a portion of the infrared spectrum for one camera anda visible filter that blocks a portion of the visible spectrum for theother camera. Alternatively, both cameras may use wavelength filtersthat each block different wavelength ranges of infrared radiation,different wavelength ranges of visible light, or different wavelengthranges of ultraviolet radiation. For example, the cameras may includerespective filters that selectively block different wavelengths rangesof LWIR, MWIR, SWIR, MWIR+LWIR, SWIR+MWIR, or the like.

Sensor 44 may include any mechanism capable of detecting radiation ofinterest, for example, in the form of an image formed by the inputoptics, and converting the detected radiation into a signalrepresentative of the detected radiation or image. The sensor may createa video signal by detecting a series of images over time, such as at aconstant rate of image detection. The sensor generally includes atwo-dimensional array of photosensitive elements or pixels. The sensormay, for example, include a cooled or uncooled infrared sensor (such asa focal plane array or microbolometer), a visible light sensor (such asa CCD or CMOS device), or the like. The sensors of assemblies 26, 28 maybe set or adapted to detect the same type of optical radiation and/orthe same wavelength bands (spectral ranges) of that type of opticalradiation (e.g., among others, two ultraviolet sensors, one for eacheye, two visible light sensors, one for each eye, two infrared sensors(each detecting SWIR, MWIR, and/or LWIR), one for each eye.Alternatively, the sensors may be set or adapted to detect differentwavelength bands (e.g., among others, an SWIR sensor and an LWIR sensor,an SWIR sensor and an MWIR sensor, an MWIR sensor and an LWIR sensor, avisible light sensor and an infrared (SWIR, MWIR, and/or LWIR) sensor,an ultraviolet sensor and a visible light sensor, an ultraviolet sensorand an infrared sensor, and so on. One or more of the sensors also maysimultaneously detect multiple wavelength bands (e.g., among others,SWIR and LWIR, MWIR and LWIR, or one or more infrared bands andvisible). Multispectral sensors may allow greater flexibility,especially if used in conjunction with exchangeable filters, so that thebinoculars can be configured and reconfigured for different uses. Someembodiments may include a third (or higher number) sensor of anywaveband, including ultraviolet, visible, or infrared to provideadditional cues. The third or high order sensor may share an inputoptical axis with the first or second sensor, or may have an inputoptical axis that is distinct, such as parallel and offset horizontallyand/or vertically from the other input optical axes. The sensors may beindependent or coordinated.

Cameras 56, 58 each may be configured to detect radiation from a similarfield of view. Images detected by the left and right cameras may be ofsimilar size, shape, and/or magnification. Accordingly, in some cases,images or video collected over the same time period by left and rightcameras may represent pairs of left and right stereoscopic images and/orleft and right videos that are stereoscopic.

Cameras 56, 58 may be configured to detect any suitable types andwavelength ranges of optical radiation, such as the same or differenttypes and/or ranges. For example, left and right (or right and left)cameras respectively may be an ultraviolet camera and a visible lightcamera, an ultraviolet camera and an infrared camera, a visible lightcamera and an infrared camera, a pair of ultraviolet cameras, a pair ofvisible light cameras, or a pair of infrared cameras, among others. If apair of infrared cameras, the cameras may, for example, be a pair ofSWIR cameras, a pair of MWIR cameras, a pair of LWIR cameras, an SWIRcamera and an MWIR and/or LWIR camera, an MWIR camera and an LWIRcamera, and so on.

Display 46 may include any mechanism capable of converting the signalformed by the sensor, including a manipulated version of the signalformed by controller 50, into visible light images, capable of beingdetected by the human eye. Exemplary displays include liquid crystaldisplays (LCDs), light-emitting diode (LED) displays, organiclight-emitting diode (OLED) displays, cathode ray tube (CRT) displays,phosphor displays, and so on. The display may be described as anelectronic display. The display may be capable of generating grayscale(or monochromatic) images, color images, or a combination thereof.

The displays for the monocular assemblies may be synchronized orunsynchronized with each other. For example, the displays of system 20may or may not be refreshed at the same rate, such as in unison or inalternation. The displays may be of similar size and shape and may belocated at about the same distance from corresponding output optics 48,which may facilitate visualization of stereoscopic images or videos thatcan be utilized by the human visual system to perceive depth in theimages/videos.

One or both of the displays may be operatively connected to at least oneuser-controlled intensity adjustment mechanism. The adjustment mechanismmay be operated by a user, generally via user inputs communicated to oneor both displays through user interface 54, to alter the relativeintensity (i.e., the intensity ratio) of left video images compared toright video images presented by the two displays. Changing the intensityratio of video images presented by the two displays may, for example,facilitate or improve integration of left video images with right videoimages by the user's human visual system. The relative intensity of thedisplays may be adjusted by changing the intensity of only one of thedisplays or by changing the intensities of both displays in oppositedirections (i.e., making one of the displays brighter and the other ofthe displays less bright). The intensity of video images presented byone of the displays may (or may not) be adjustable by a userindependently of the intensity of video images presented by the otherdisplay. In some cases, the intensity of each display may be adjustableindependently of the intensity of the other display. Independentlyadjustable intensities may be particularly useful in embodiments inwhich the two monoculars are used to image different wavebands.

The left and right displays may be configured to present respective leftvideo images and right video images. The left video images may bepresented based on the left video signal, and the right video images maybe presented based on the right video signal. Accordingly, the leftvideo images correspond to the left input optical axis of the leftcamera and the right video images correspond to the right input opticalaxis of the right camera. In exemplary embodiments, there is nosubstantial blending of the left video signals with right video signalby the system: the right video signal makes no substantial contributionto the left video images and the left video signal makes no substantialcontribution to the right video images. Instead, integration and/orcomparison of left and right video images may be performed by the humanvisual system.

Output optics 48, also termed an eyepiece, may include one or moreoptical elements for gathering, directing, filtering, and/or focusingvisible light from a display such that it may be viewed by a user's eye,thereby allowing or facilitating a user to see visible light imagesformed by the display. For example, the display and output optics may beselected and disposed so that a user's eye will perceive a magnifiedvirtual image of the display (e.g., by positioning the display insidethe focal point of a suitable convex eyepiece lens). Accordingly, theeyepiece may include any combination of the optical elements describedabove for the input optics. The eyepiece may define an optical pathtraveled by visible light from the display to the user's eye. Also, theeyepiece may form an optical window through which visible light emergesfrom a monocular assembly. Each eyepiece 48 and its associated display46 may be described as a left or right visualization unit (60 or 62).

The input optical axes 30, 32 may have any suitable relation to oneanother and to output optical axes 38, 40. The spacing of the input axesmay be fixed or adjustable. If adjustable, the spacing (e.g., thehorizontal separation) between the cameras of assemblies 26, 28 may beadjustable, generally while keeping input axes 30, 32 parallel to oneanother. If adjustably spaced, one camera may be fixed and the othermovable, or both cameras may be movable with respect to support assembly29. If both cameras are movable, they may be movable independently ofone another or movement of both cameras may be coupled. Adjustment ofthe spacing between the cameras (and thus between input axes 30, 32) maychange the apparent depth of a scene perceived by a person using system20. The spacing between input axes 30, 32 may be about the same as,greater than, or less than the spacing between output axes 38, 40. Forexample, the spacing may be between about 50 millimeters and 150millimeters, among others. Input axes 30, 32 may be parallel to outputaxes 38, 40. Furthermore input axes 30, 32 may define a first plane andoutput axes may define a second plane, and the first and second planesmay be parallel, such as substantially coincident or offset verticallyfrom one another when the first plane is horizontal. Increasing thespacing between the input axes may facilitate use of larger objectivelenses, increasing light collection (which may be especially usefulunder low-light conditions).

Cameras 56, 58 and visualization units 60, 62 each may be focused by anysuitable mechanism. Focusing may be driven manually or with a motor,among others. Furthermore, focusing of each camera or visualization unitmay be controlled manually or may be controlled automatically bycontroller 50 (e.g., to provide autofocusing).

Each camera may be focused independently or the cameras may be focusedin unison. The focus may be adjusted by driving relative motion of theobjective and sensor of the camera, generally to change their separationon the optical path. Accordingly, the objective, the sensor, or both maybe moved with respect to support assembly 29. In some cases, system 20may include a single focusing mechanism 64 capable of moving, at thesame time (indicated at 66), both sensors 44 (or both objectives) closerto or farther from the objectives (or sensors). For example, bothsensors may be attached to a carriage 68 that is mounted movably to thesupport assembly, to permit translational motion of the carriage thatcoordinately changes the length of the optical path from each sensor toits corresponding objective. Alternatively, or in addition, bothobjectives may be movable in unison by a single focusing mechanism (seeSection III).

Visualization units 60, 62 may be focused coordinately or independentlyfrom one another. However, because the left eye and the right eye of aperson may require a different correction, the ability to focusvisualization units 60, 62 independently is generally preferable. Thefocus (also termed the diopter) may be adjusted by driving relativemotion of the display and the eyepiece, to change their separation onthe output optical path. In some cases, system 20 may include a pair offocusing mechanisms 70, 72 capable of independently moving, with respectto support assembly 29, a display (or eyepiece; see Section III) closerto or farther from its corresponding eyepiece (or display). The focusingmechanisms may be described as a dual diopter adjustment, with thediopter adjustments for units 60, 62 being independent of one another.Exemplary diopters that may be achieved by the focusing mechanisminclude a negative diopter (e.g., −5, −4, −3, −2, and/or −1), a positivediopter (e.g., +1, +2, +3, +4, and/or +5), or any combination thereof.

Visualization units 60, 62 also may be adjustable to alter their spacingfrom one another (and particularly the spacing of output axes 38, 40, tomatch the spacing (i.e., the interpupillary distance (from about 50 to75 millimeters)) between a given user's eyes. Both units may be movablewith respect to support assembly 29 or one unit may be fixed and theother movable. If both are movable, the movement may be coupled orindependent from one another. For example, system 20 may include anadjustment mechanism 74 that coordinately (i.e., simultaneously) movesboth units, indicated at 76. (An adjustment mechanism that permitsindependent movement of visualization units is described in SectionIII.) Movement of the visualization units may be in a directionorthogonal to output optical axes 38, 40 and parallel to a plane definedby these axes. One or both visualization units may be moved withoutchanging the rotational disposition of each display (as might occur ifassemblies 26, 28 were pivoted relative to one another via a connectinghinge to change the spacing of the eyepieces).

Support assembly 29 may have any suitable structure. The supportassembly (and/or system 20) may be configured to be hand-held,head-mounted, mounted to a vehicle (e.g., an aircraft, land vehicle, orwatercraft), or the like. Accordingly, the support assembly (and/orsystem 20) may provide one or more mounting brackets, straps (forplacement around the head, neck, arms, chest, etc.), arms for placementover ears, clips, etc. In some embodiments, the support assembly may bedesigned to be supported by a person's head and/or by a head cover(e.g., strapped or clipped to a helmet).

The binocular system may be sealed or sealable, such that the system iswatertight and/or resistant to damage by sand or dust. In someembodiments, the system is sealed to restrict water entry, to permitsubmersion of the system in water without damage to internal components,such as cameras, displays, the controller, or other electronics. Toprovide a watertight system, the support assembly may be fluid-tight andmay form a fluid-tight seal with the input and output optics.Alternatively, or in addition, the system may include a removable orintegral cover for the input optics and/or the output optics that canform a fluid-tight seal with the support assembly. For example, thesystem may include one or more caps that can be secured removably overeach eyepiece or objective, to block water inflow, and that may clip orotherwise attach to the support assembly. In some cases, the system mayinclude an integral, optically transmissive window disposed over eachobjective and forming a non-moving seal that allows the system to besubmersed in water and/or operate in extreme sand/dust environments.

Controller 50 may be any mechanism or collection of mechanismsresponsible for manipulation of data and communication of signalsbetween or among system components. The controller may be responsiblefor controlling operation of any suitable system components, forexample, the cameras, the visualization units, and so on. Accordingly,the controller may be in communication with the sensors and displays, toreceive signals from and/or send signals to the sensors and displays,and may be capable of controlling and/or responding to operation of thesensors and/or displays. Also, the controller may be responsible formanipulating (processing) image data (i.e., the representative videosignals) received from the cameras before the signals are communicatedto the visualization units, to drive formation of visible light imagesby the displays. The controller may include one or more processors(e.g., digital processors) for data manipulation and also may includeadditional electronic components to support and/or supplement theprocessors. In some embodiments, each monocular assembly may include arespective controller subunit (77A or 77B) that is responsible foroperation of the sensor and display of the monocular assembly. With thisdivision of labor, the controller subunits can operate in parallel tocontrol generation of respective left and right video images by thedisplays. However, the controller subunits may be in communication withanother. For example, one of the subunits may be a master and the othera slave controlled by the master. Also, one of the controller subunits(e.g., the master subunit) may be responsible for receiving inputs froma user via user interface 54.

Power supply 52 may be any mechanism for providing operating power tothe system. The power supply may be line power, one or more batteries,or a combination thereof, among others. The power supply may be a sourceof power for the controller, sensors, displays, one or more focusingmechanisms, an illuminator, a rangefinder, or any combination thereof,among others. The power supply may include a central supply that is useddirectly or indirectly by all power-consuming components of the systemand/or may include a plurality of individual power supply units that areintegral to and/or dedicated to different components. The system mayhave an off mode, an on mode, and, optionally, a lower-power or sleepmode, among others.

User interface 54 may be any mechanism or combination of mechanisms thatpermits a user to communicate with controller 50 and/or otherdevices/mechanisms of the system, such as to set preferences, navigatethrough menus, select options, adjust a focus, adjust the intensity of adisplay, and so on. Exemplary user interfaces include one or moreswitches, buttons, levers, knobs, or dials; a joystick; a touchscreen;or any combination thereof, among others.

System 20 may be equipped with at least one data-sharing mechanism, suchas at least one data port 78. The port may be a wired or wireless port.The port may be used for downloading and/or uploading data. For example,the port may be used to download instructions to controller 50, such asto provide a software update or to add additional functionalcapabilities to the controller. Alternatively, or in addition, the portmay be used to upload data, such as image data (e.g., a dual-channelvideo signal representing left and right video signals), to othermachines and/or users. The image data may be uploaded to an externalstorage device or an external display, among others. In some cases, theimage data may be uploaded as a dual-channel video signal (i.e., a videostream containing a left video signal and a right video signal). Thevideo stream may intersperse a left video signal and a right videosignal, such as rapidly alternating left video and right video (e.g.,alternating individual left and right images in the video stream). Thevideo stream may be communicated to a three-dimensional display (e.g.,to be viewed with appropriate 3D glasses) and/or to a remote pair ofvisualization units analogous to those of system 20, among others. Thevideo stream may be communicated via data port 78 in real time (i.e.,substantially immediately upon creation) or may be stored first insystem 20 for a selectable/adjustable time interval beforecommunication.

System 20 also may be equipped with at least one radiation source 80,for example, an illuminator to actively illuminate at least a portion ofa scene and/or a designator to actively designate a target or targets.The radiation source may emit ultraviolet radiation, visible light,infrared radiation, or any combination thereof. The radiation source maybe a laser, a light emitting diode, an incandescent light, or afluorescent light, among others. Illumination provided may be continuousor intermittent (i.e., at regular or irregular intervals, such as by astrobe) when the radiation source is activated. Activation of theradiation source may be controlled by the user, the controller, or acombination thereof, among others.

System 20 further may be equipped with a range-finding mechanism 82. Arange-finding mechanism is any mechanism that measures or enablesmeasurement by a user of the distance from system 20 to an object in thescene and/or the distance between objects in the scene. Exemplaryrange-finding mechanisms include a laser rangefinder (for measuring thedistance from system 20 to an object) or a reticle (for measuring thedistance between objects in a scene). If a reticle is included, thereticle may be provided by one or more visualization units, such asformed by a display or included in an eyepiece. Another exemplaryrange-finding mechanism utilizes the controller to process image datafrom left and right cameras to determine the distance to an object in ascene by the extent of positional disparity exhibited by the object(e.g., the position of the object relative to background) in left andright images of the scene detected by the corresponding cameras.

System 20, particularly handheld embodiments, further may be equippedwith image stabilization mechanisms to reduce image blurring and/orother artifacts caused by unintended motion of the binoculars,particularly rotation about axes oriented left-right and up-down (“pan”and “tilt,” or “pitch” and “yaw”). Stabilization may be accomplishedusing any suitable mechanism(s). In some embodiments, stabilization maybe accomplished by increasing the binoculars' moment ofinertia—resistance to rotation—around these two axes, for example, byincreasing the off-axis mass of the binoculars, by adding one or moregyroscopes (which must be powered), and so on. Alternatively, or inaddition, stabilization also may be accomplished by sensing motion andactively adjusting the orientations and/or positions of opticalelements, such as lenses and/or sensors, to compensate. Stabilizationalso may be accomplished after the image is collected but before it isdisplayed by shifting successive displayed images left or right, and/orup or down, frame to frame to compensate electronically for unintendedmotion that has not been prevented.

II. CONTROLLER CAPABILITIES

This section describes exemplary controller capabilities that may beincorporated into the binocular system. The capabilities may be usedtogether in any suitable combination and may be included in a binocularsystem having any combination of components and features of the presentdisclosure.

The controller may control generation of grayscale/color images by eachdisplay. The term “grayscale/color” means grayscale (or monochrome),color, or a combination of grayscale and color. The term “grayscale”also may be described as “black and white,” which generally includesdifferent shades of gray from white or near white to black or nearblack, but without chromatic variation. The term “color” generallyincludes one or more non-grayscale colors, such as one or more or a setof primary or secondary colors (e.g., red, blue, yellow, green, orange,violet, or a combination thereof), among others. Color video images maybe a combination of grayscale and color, such as images that aresubstantially monochromatic but with color coding added to highlightregions (e.g., image pixels) of a scene that meet one or more predefinedconditions (e.g., pixels having values that exceed a threshold).

The controller may assign grayscale intensities and/or colors to imagedata from each sensor according to default instructions and/or userinput, among others. For example, the controller may utilize a look-uptable and/or implement an equation to convert values in therepresentative signal from a sensor to grayscale/color pixel data to beimplemented by a display. In any event, the controller may utilize thesame grayscale/color palette for both displays or may have the abilityto utilize different palettes. For example, the controller may contain aset of palettes from which one or more palettes can be selected for usein displaying images. The same or different palettes may be selected forthe left display and the right display, to present images created withthe same palette or different palettes to each eye (e.g., a grayscalepalette for the left display (and left eye) and a color or grayscaleplus color palette (e.g., a color-coded scheme) for the right display(and right eye), or vice versa). The palettes to be utilized for imagegeneration by the displays may be selected by a user (such as via theuser interface) or may be selected automatically by the controller(e.g., selected dynamically based on the signal from the sensor(s)).

The controller may be programmed to implement various colorizingtechniques using the appropriate palette(s). In other words, thecontroller may be capable of instructing the displays to generategrayscale images, color images, and/or grayscale images with color addedselectively. In a basic scheme, the controller assigns grayscaleintensities to pixels of an image in a manner directly or inverselyrelated to radiation intensities detected by the sensor (e.g., directlyrelated for one of the displays and inversely related for the otherdisplay). For example, if this scheme is used for generating visiblethermal images from detected infrared radiation, the hotter areas of theimages are lighter and the colder areas are darker, to provide a“white-hot” polarity, or vice versa, to provide a “black-hot” polarity.The controller may drive generation of images with white-hot polarity orblack-hot polarity by each display. In some cases, the controller maycause a white-hot polarity to be displayed to one eye and a black-hotpolarity to be displayed to the other eye. Accordingly, the displays maypresent left and right video images with inverse grayscale polarity.This approach may facilitate recognition or rejection of regions ofintermediate “temperature,” because they will be displayed with similarintensities to both eyes.

Thermal (or other radiation) intensities can be color-coded in onechannel only (left or right) or in both channels (left and right) usinga color palette (e.g., with blue being coldest, green warmer, yellowstill warmer, orange hotter, and red hottest, or any combinationthereof, among others). Furthermore, thermal (or other radiation)intensities can be color-coded using a combination grayscale plus colorpalette, with one or more thresholds to define when to use grayscale orcolor for individual pixels. For example, low and intermediate thermal(or other radiation) intensities can be represented in grayscale whileintensities above a threshold can be represented in color (e.g., red),such as to identify the hottest (or most intense) object(s)/region(s) inan image. Alternatively, or in addition, thermal (or other radiation)intensities below a threshold can be assigned another color (e.g., blue)to identify the coldest (or least intense) object(s)/region(s) in animage.

The controller may be programmed to color-code movement in displayedimages. The color-coding may be performed in one channel (left or right)or in both channels (left and right). The controller may assign a colorto an object that is moving with respect to a background and/or withrespect to the user. For example, moving objects may be displayed incolor (by one or both displays) and nonmoving objects displayed ingrayscale or in a distinct color(s) from the moving object. A singlecolor may be used to identify moving objects or more than one color maybe used to indicate the speed and/or direction with which each object ismoving. For example, a faster object may be presented in red and aslower object in green. The speed of an object can be determined byestimating the distance to the object with the binocular system (e.g.,by positional disparity and/or with a rangefinder) and the rate at whichthe size or position of the object changes in the field of view.Alternatively, or in addition, objects moving toward or away from theuser may be assigned respective distinct colors, for example, an objectmoving toward the user may be color-coded with red and an object movingaway from the user with green. Object movement may be determined byprocessing image data for a series of images from one or more sensors.An object that increases (or decreases) in size over time can becolor-coded as moving toward (or away from) the user. Alternatively, orin addition, active rangefinders could be used to collect suchinformation.

The controller may be programmed to color-code distance in imagesdisplayed in only one channel (left or right) or in both channels (leftand right). In particular, objects/features in the images may becolor-coded according to their distance from the system/user.Color-coding may, for example, be implemented by adding color to agrayscale image, with one or more ranges color-coded. As an example,objects that are closer than (or greater than) a threshold distance fromthe user may be assigned a color. Different colors may be assigned forobjects disposed within distinct ranges from the user. The distance toan object may be estimated by processing left and right image data, tofind a positional disparity exhibited by the object in left and rightimages. Alternatively, or in addition, the distance to an object may bedetermined with a range-finding mechanism.

The controller may be programmed to provide an electronic zoom functionthat achieves a stepped change and/or a smooth change in magnificationof displayed images. The zoom function may be actuated via a userinterface that can be utilized to instruct the controller to increase ordecrease the magnification.

The controller may be programmed to implement any suitable algorithmsfor processing image data. In some embodiments, the controller may becapable of adjusting the relatively intensities of image pixels, whichmay be implemented to improve image quality, reduce noise, lessen imagepixelation, highlight image features, reduce the impact of flashes ofradiation (scintillation mitigation), or any combination thereof, amongothers. For example, the controller may be configured to smooth out thequantized range caused by range pixelation. The controller also oralternatively may be capable of imposing a nonuniform correction (NUC)on image data to correct for nonuniform sensitivities or drift of thephotosensitive elements of one or more sensors. Other algorithms maypermit processing of one or more images from a scene to identify and/orcharacterize objects in the scene. Exemplary objectidentification/characterization may include motion detection, intentdetermination, facial recognition, or the like. For example, thealgorithm may permit tracking an object within the field of view. Theobject may be identified to the controller by the observer (e.g., viathe user interface) or the controller may identify the object byprocessing image data. In any event, the controller may display cues forthe motion of the object, to direct the observer to slew in thedirection of object motion.

The controller may be programmed to drive presentation of otherinformation by one or both of the displays. The other information may(or may not) be presented on one or both displays in association withvideo images. The other information may be presented adjacent displayedimages (e.g., in a top, bottom, or side bar) and/or partially orcompletely overlapping displayed images. Accordingly, the otherinformation may be presented as an overlay that is fused with displayedimages and at least partially blocks, obscures, replaces, and/or altersa region of displayed images. Exemplary other information that may bepresented may be conveyed by symbols (e.g., characters (such asalphanumeric and/or other characters), icons, etc.), geometric shapes(e.g., line segments, circles, rectangles, etc.), and the like. Theother information may be used for any suitable purpose, such as to offermenus and options for system operation, to display selected preferencesand/or status information, to provide a legend summarizing the meaningof colors and/or symbols (especially if variable), to indicate anoperating mode, to identify an object or image region, to indicateobject range(s) with symbols, to mark a tracked or moving object or apath thereof, to prompt the user to act, or any combination thereof,among others.

The controller may drive presentation of the other information in bothdisplays at the same time. The other information may be presented at thesame relative position on both displays, such that there is no binoculardisparity when the information is viewed by a pair of eyes.Alternatively, the other information may be presented with binoculardisparity in left images relative to right images, to give theinformation a perceived depth, for a three-dimensional effect. Forexample, symbols may be presented with positional disparity in leftvideo images relative to right video images, so that the symbols areperceived as three dimensional (i.e., as having depth) and/or as beingdisposed at one or more positions along a depth axis.

However, presenting the other information on both displays concurrently(i.e., in duplicate), in combination with left and right video images,can be distracting to the user. For example, the human visual system ofthe user may have difficulty uniting duplicated information from thedisplays and thus may perceive the duplicated information as a pair ofoffset copies rather than one copy. To avoid this problem, thecontroller may be programmed to drive presentation of other informationby only one of the displays at a time as both displays present leftvideo images and right video images, such that the other information isseen only with one eye when the video images are viewed with both eyes.With this configuration, the user can view stereoscopic left and rightvideos of detected radiation binocularly while the other information isviewed monocularly. In some embodiments, the user may be allowed toselect which one of the displays is used for presenting otherinformation.

The binocular system may be used when turned upside down (inverted),such that the left eye views the right display and the right eye viewsthe left display. The controller may be programmed to respond to theorientation of the system by automatically orienting displayed symbols,such as alphanumeric characters, in correspondence with the normal orinverted orientation of the binocular system. As a result, the symbolsmay be oriented correctly (i.e., right side up) for viewing by the userin both system orientations. Stated differently, alphanumeric charactersmay be flipped automatically for presentation in a right-side uporientation to a user when the binocular system is turned upside down.The system may be equipped with an orientation sensor, such as anaccelerometer, a gyroscope, or an orientation-dependent switch, amongothers, to automatically determine whether the system is being used in anormal or inverted orientation. In some cases, rather than flipping thecharacters automatically, alphanumeric characters may be flipped inresponse to a user input that informs the controller of the orientation(i.e., right-side up or upside down) of the binocular system. For thesecases, the user may serve as an orientation sensor.

The controller may be programmed to blend video signals detected with apair of cameras, such as a left/right camera and a third camera. Thepair of cameras may be configured to detect respective wavelength bandsthat are different from each other. The controller may blend videosignals detected by a visible light camera and an infrared camera (e.g.,an SWIR, MWIR, and/or LWIR camera), an ultraviolet camera and a visiblelight camera, an ultraviolet camera and an infrared camera (e.g., anSWIR, MWIR, and/or LWIR camera), distinct infrared cameras (e.g., anSWIR camera and an MWIR camera, an SWIR camera and an LWIR camera, anMWIR camera and an LWIR camera, two SWIR/MWIR/LWIR cameras, etc.), andso on. The pair of cameras may share an input optical axis and/or one ormore optical elements for their respective input optics. Alternatively,the pair of cameras may have offset optical axes and/or respective inputoptics that are not shared with one another.

The controller may be programmed to accentuate contributions from withinparticular wavelength bands (e.g., to highlight humans, functioningequipment, and/or the like, based on their temperature).

III. EXAMPLES

The following examples describe selected aspects and embodiments ofbinocular systems. These examples are intended for illustration only andshould not limit or define the entire scope of the present disclosure.

Example 1 Exemplary Infrared Binocular System

This example describes an exemplary embodiment of an infrared binocularsystem 120; see FIGS. 2-6.

FIGS. 2 and 3 show respective isometric and sectional views of binocularsystem 120. The system includes a pair of monocular assemblies 122, 124each capable of detecting incident infrared radiation received on inputoptical axes 126, 128 from a distant scene and presenting a visiblelight representation of the detected radiation to an observer. Themonocular assemblies are mirror images of one another and containsubstantially identical components.

Each assembly includes a thermal camera 130. The camera receives andfocuses incident infrared radiation using objective 132. The radiationis focused onto a focal plane array 134 of the camera, which creates asignal (i.e., image/video data) representative of the detectedradiation, which is communicated to a controller subunit 136.

Controller subunit 136 may process the signal (e.g., to assigncolor/grayscale to parts of the signal, add an overlay, etc.) and thenuses the signal to drive presentation of visible light images by avisualization unit 138 of assembly 122 or 124. The visualization unitincludes a display 140 that forms the images and an eyepiece 142 thatfocuses the formed images onto a user's left or right eye.

Each visualization unit also may incorporate an eyecup 144. The eye cupmay be formed of a resilient material, such as an elastomer, to permitthe eye cup to conform to the contours of a user's face when the eye cupis pressed against the face around the eye. The eye cup may function tospace the user's eye reproducibly from the eyepiece, to achieve properfocus. The eye cup also may form a substantial seal generally around auser's eye to restrict leakage of light from the eyepiece during use, tomaintain covertness.

System 120 also includes various mechanical and electronic controls thatcan be operated by a user (see FIG. 2). For example, a focusing knob 146operates a mechanical focusing mechanism 148 for both objectives. Othercontrols that provide communication with the system's controller includea joystick 150, a nonuniform correction (NUC) button 152, and anelectronic zoom button 154. A power switch 156 turns the system on andoff.

FIGS. 3 and 4 show aspects of the focusing mechanism for objectives 132.Each objective is held in place by a holder 158 received in a respectivebarrel 160 formed by the system's frame 162. Each holder 158 is inthreaded engagement with barrel 160. The holder includes a gear 164 (atoothed wheel) extending around the holder (see FIG. 4). Knob 146 isconnected to gear 164 of each holder 158 via shared intermediate gears166, 168. Turning knob 146 causes coupled rotation of holders 158 ofboth monocular assemblies. Due to the threaded engagement, rotation ofholders 158 causes the objectives to move along barrels 160, eithercloser to or farther from their associated sensors, according to thedirection of rotation of knob 146, which provides simultaneous focusadjustment for both cameras.

FIG. 5 shows aspects of an interpupillary adjustment mechanism 180 ofsystem 120. Mechanism 180 permits visualization units 138 to berepositioned along an adjustment axis 182 that is orthogonal to a planedefined collectively by the optical axes of units 138. In this view,visualization units 138 have been partially disassembled, with eye cups144 (see FIGS. 2 and 3) removed from both units, and a housing 184removed from only one of the units. Visualization units 138 may haveopposing hooks 186 that hook onto rails 188 provided by the system'sframe, to permit each unit to slide along the rails. A separate detentmechanism 190 for each unit restricts sliding motion of the unit untilsufficient force is applied to overcome the holding action of the detentmechanism. The detent mechanism includes teeth 192 formed on theunderside of unit 138 and engaged by one or more complementary teeth 194provided by a leaf spring 196. In some embodiments, only one of thevisualization units may be movable to provide interpupillary adjustment.

FIG. 6 shows a sectional view of selected aspects of visualization unit138.

Each unit includes a diopter adjustment mechanism 200 that permits theunit to be used, in some cases, without a user's corrective lenses(e.g., glasses). The diopter adjustment mechanisms of units 138 can beadjusted independently of one another, to apply a different correctionfor each eye of a user. Eyepiece lenses 202, 204 are mounted in a holder206 that is in threaded engagement, indicated at 207, with a sleeve 208disposed within the unit's housing. The sleeve is prevented fromrotating with respect to the system's frame. Holder 206 includes a dial209 that facilitates turning the holder manually to change the threadedposition of the holder with respect to sleeve 208, thereby moving theholder and its lenses either closer to or farther from display 140, toadjust the focus.

Mechanical features may prevent the complete unscrewing of the holderfrom the unit and also limit the adjustment range (such as to determinethe diopter values that are permitted). Dial 209 has a tab that permitsno more than about one complete rotation with respect to sleeve 208. Thethread pitch of threaded engagement 207 determines the extent of diopteradjustment produced by the complete rotation.

Example 2 Exemplary Interpupillary Adjustment Mechanism

This example describes another exemplary embodiment of an infraredbinocular system 220 with an alternative interpupillary adjustmentmechanism 222; see FIG. 7.

The binocular system includes a pair of visualization units 224, 226each hooked onto and slidable on a pair of rails 228. The visualizationunits are connected via a thumbwheel assembly 230 that forms a spanbetween the two units. Both ends of the thumbwheel assembly are inthreaded engagement, indicated at 232, with a visualization unit.Rotation of the thumbwheel changes the length of the span between theunits, which coordinately drives the units closer together or fartherapart, depending on the direction of thumbwheel rotation. In othercases, one of the visualization units may be fixed and the othermovable.

Example 3 Exemplary Binocular System with Separate Units for Detectionand Image Display

This example describes an exemplary binocular system 320 divided intoseparate units; see FIG. 8.

System 320 includes a camera unit 322 and a presentation unit 324. Thecamera unit is equipped with at least two cameras 326, 328 adapted tocreate left and right video signals, which are communicated to thepresentation unit for presentation of left and right videos by displays330, 332 based on the video signals. Alternatively, or in addition, theleft and right video signals may be communicated to a 3D display. One orboth units 322, 324 may include a controller 334, 336 that manipulatesthe video signals and/or drives presentation of video images by thedisplays. Units 322, 324 may communicate with one another via a wired orwireless mechanism, indicated at 338.

The units may be movable independently of one another along and/or aboutmultiple axes. With this arrangement, the camera unit can be mountedremotely from a user, such as on a land-based vehicle, an aircraft, abuilding, a geographical feature, and so on. For example, the cameraunit may be supported by a gimbal system that controllably adjusts theorientation of the camera unit independently of the presentation unit.System 320 thus may be utilized on an aircraft as an enhanced visionsystem and/or as part of a navigation system.

Example 4 Exemplary Binocular Systems with Additional Cameras

This example describes exemplary binocular systems with more than twocameras; see FIGS. 9 and 10.

FIG. 9 shows a schematic view of an exemplary binocular system 420incorporating at least one additional camera relative to system 20 (seeFIG. 1). The system may receive incident light from a scene via left andright optical assemblies 422, 424. One or both of the optical assembliesmay be part of two cameras, such as cameras 426, 428 for assembly 422,and cameras 430, 432 for assembly 424. The two cameras on the left, 426and 428, may share the same input optical axis for receiving incidentlight, as may the two cameras on the right.

Incident light received on the left (and/or right) may be split, such aswith a beam splitter 434, to direct the light to distinct sensors 436,438 of respective cameras 426, 428 (and/or distinct sensors of cameras430, 432). The beam splitter may or may not divide the light beamaccording to wavelength. For example, the beam splitter may permitvisible light (or a first wavelength band of infrared radiation) to passthrough the beam splitter to sensor 438, while reflecting infraredradiation (or a distinct second wavelength band of infrared radiation)to sensor 436, or vice versa. In any event, sensors 436, 438 createrespective video signals, which may be communicated to a controller orcontroller subunit 440. The controller may blend the video signals, byblending images detected by sensor 436 with images detectedcontemporaneously by sensor 438. The blended images may be displayed bya visualization unit 442.

A blended image or video signal may include any image or video signalthat incorporates image data detected by more than one camera. Blendingof images or signals may utilize any suitable portion or all of eachdetected image or signal. Blending may involve any suitable computation,which may or may not be performed on a pixel-by pixel basis. Exemplaryblending operations include taking a sum, a difference, an average,implementing a threshold-dependent change, or the like. As an example, avisible image (or a first infrared image) may be blended with aninfrared image (or a second infrared image) by generating the visible(or first infrared) image in grayscale while color-coding pixels that,in the corresponding infrared (or second infrared) image, are above (orbelow) a threshold value. In some embodiments, a controller may beprogrammed to display the images from two cameras (such as cameras 426,428) separately instead of or in addition to blending video signals. Forexample, the controller may alternate display by a visualization unit ofvideo or images from the two cameras.

In alternative embodiments, sensor 436 may be transmissive for thewavelength range to be detected by sensor 438. The sensors thus may bedisposed on substantially the same optical path, with the array ofphotosensitive elements of sensor 436 overlying the other sensor'sarray. With this configuration of sensors, beam splitter 434 may beomitted.

FIG. 10 shows a schematic view of another exemplary binocular system 520incorporating at least one additional camera relative to system 20 (seeFIG. 1). The system may include at least three cameras 522, 524, 526,each equipped with separate input optics 528, 530, 532 and sensors 534,536, 538. The third (or higher order) camera may be integral to thesystem or may be a module that can be added and removed. A controller540 may blend video signals from any combination of cameras, such ascameras 522, 524, for display by a visualization unit 542. The third (orhigher order) camera may have an input optical axis that is parallel tothe input optical axes of the first and second cameras. The inputoptical axis of the third camera may or may not be coplanar with theinput optical axes of the first and second cameras. The input opticalaxis of the third camera may be spaced horizontally and/or verticallyfrom the axes of the first and second cameras.

The use of at least three cameras may permit various types of blendedvideo signals to be created by a controller, to drive presentation ofblended images by the displays. For example, left and right visibleimages (from detected visible light) may be blended on only one side(left or right) or on both sides (left and right) with detected infraredimages (SWIR, MWIR, and/or LWIR). Alternatively, left and right infraredimages may be blended on only one side or on both sides with visibleimages (from detected visible light). As another example, left and rightinfrared images (from detected SWIR, MWIR, and/or LWIR wavelength bands)may be blended on only one side or on both sides with infrared imagesdetected from at least one different wavelength band, such as LWIRimages on the left and right blended with SWIR images on only the leftor right (or both left and right).

Example 5 Exemplary Binocular System with Optically Combined Images

This example describes an exemplary binocular system 620 that opticallycombines detected images with images formed by focused incidentradiation; see FIG. 11.

System 620 may be structured generally as described for system 20 ofFIG. 1. However, incident radiation is split by a beam splitter 622 tofollow distinct paths 624, 626. Radiation traveling on path 624 isdirected to an eyepiece 628 as a bypass image formed of visible light.In contrast, radiation traveling on path 626 is detected by a sensor630, and the detected image is reproduced with visible light by adisplay 632 that is also operatively connected to eyepiece 628. As aresult, reproduced images (e.g., from detected visible light or infraredradiation) and bypass images are combined at the (left and/or right)eyepiece to form optically blended images for the user.

Example 6 Selected Aspects and Applications

This example describes selected aspects and applications of thebinocular system disclosed herein.

Exemplary binocular systems in accordance with the present disclosuremay include one or more of the following features:

-   (i) IR binocular imaging using HVS to perceive 3D depth cues;-   (ii) Separate left/right displays using HVS to perceive 3D;-   (iii) Two camera (any waveband) binocular video imaging using HVS to    perceive 3D;-   (iv) Two camera (different wavebands) binocular imaging using HVS to    perceive 3D;-   (v) Three camera imaging system: two cameras give binocular 3D,    third camera adds additional cues;-   (vi) True 3D depth perception head-mounted system providing IR    situational awareness;-   (vii) Passive range finding using binocular disparity; and-   (viii) Relative distance cueing in display.

The binocular system may be used for any suitable applications. Anexemplary application of the system includes use as an aid for walkingat night; for example, the IR binocular system may be mounted on ahelmet to provide depth perception at night. Other exemplaryapplications may include military, safety, firefighting, border andperimeter control, hunting, and/or bird watching (e.g., night birds suchas owls), among others. Exemplary applications also may includedetection of disturbed earth (e.g., to find buried explosive devices orother buried objects, graves, etc.). Further exemplary applicationsinclude detection of gas emission/leakage (e.g., detection of carbondioxide, sulfur hexafluoride (SF₆), etc.). The gas emission may, forexample, be produced by an illegal manufacturing facility (such as fordrugs, explosives, or the like).

The cameras of the binocular system may be configured to detectdifferent wavelengths that respectively (a) include or exclude aRestrahlen (commonly spelled “reststrahlen”) band of soil or (b) includeor exclude an absorption band of a gas of interest. For example, thecameras may include respective distinct LWIR filters that include orexclude the Restrahlen band or absorption band.

A Restrahlen band (also termed a Restrahlen feature) of a material is awavelength band of optical radiation where the ability of the materialto reflect optical radiation increases. If the material is a goodabsorber in this band, the emission of optical radiation by the materialdips in the Restrahlen band. Generally, the emission of thermalradiation emitted from soil changes with the soil's grain size in aRestrahlen band for the soil, with smaller grains exhibiting higheremission than larger grains. Disturbing soil (such as by burying anobject) can locally decrease the grain size near the surface, which canresult in higher emissivity of thermal radiation in a Restrahlen band ofthe soil.

The position of the Restrahlen band may be dependent on the soilcomposition. For example, silicate-rich soils have a differentRestrahlen band than carbonate-rich soils. Accordingly, suitable filters(and/or sensors) may be selected according to soil composition.

In any event, one (or more) of the cameras may be configured to detectthermal radiation in a Restrahlen band of soil (e.g., in the LWIRrange). In some embodiments, both of the cameras may be configured todetect in the LWIR range and only a first camera may detect thermalradiation substantially in the Restrahlen band. The second camera may beconfigured to selectively detect thermal radiation that excludes theRestrahlen band, which may provide a control or reference for variationsin LWIR radiation that are not dependent on differences in grain size.

The following illustration for detection of disturbed soil is exemplary.Quartz-rich soils exhibit a Restrahlen band between about 8.2 and 9.5μm. Two LWIR cameras may be utilized in the binocular system. One of thecameras may include a high cut-off filter that blocks LWIR of greaterthan about 9.5 μm, to detect variations in grain size near the surface.The other camera may have a low cut-off filter that blocks LWIR of lessthan about 9.5 μm.

Gas detection may be performed with the binocular system. One (or both)of the cameras may be configured, such as with a suitable filter, todetect radiation in a wavelength range overlapping an absorption band ofa gas of interest (e.g., carbon dioxide, sulfur hexafluoride, or thelike). The other camera may be configured to detect radiation in adistinct wavelength range, such as a wavelength range that substantiallyexcludes the absorption band. If the gas is present, it will absorbthermal radiation emitted by objects behind the gas in the field ofview, to reveal the presence of the gas.

The following illustration for detection of a gas of interest isexemplary. Sulfur hexafluoride is a potent greenhouse gas that hasnumerous uses in manufacturing and in high voltage systems, amongothers. This gas has an absorption band in the LWIR range centered atabout 10.5 μm. Two LWIR cameras may be utilized in the binocular system.One of the cameras may have a high cut-off filter that blocks LWIR ofless than about 10 μm, to permit detection of LWIR absorption by sulfurhexafluoride. The other camera may have a low cut-off filter that blocksLWIR of greater than about 10 μm, which may serve as a control orreference showing variations in thermal emission that are not dependenton the presence of sulfur hexafluoride.

Example 7 Selected Embodiments

This example describes selected embodiments and aspects of the presentdisclosure as a series of numbered paragraphs.

1. A binocular system, comprising: (A) a left camera and a right camerathat create left and right video signals from detected optical radiationreceived from about a same field of view along respective left and rightoptical axes that are parallel to and offset from each other, at leastone of the cameras including a sensor that is sensitive to infraredradiation; and (B) a left display and a right display arranged to beviewed by a pair of eyes and configured to present left and right videoimages formed with visible light based respectively on the left andright video signals.

2. The binocular system of paragraph 1, wherein the left camera isconfigured to detect a first wavelength band of optical radiation andthe right camera is configured to detect a second wavelength band ofoptical radiation, and wherein the first wavelength band and the secondwavelength band are different from each other

3. The binocular system of paragraph 1 or 2, wherein the left cameraincludes a first sensor and the right camera includes a second sensor,and wherein the first sensor and the second sensor are sensitive torespective wavelength bands of optical radiation that are different fromeach other.

4. The binocular system of any of paragraphs 1 to 3, wherein the leftcamera includes a first sensor and first input optics and the rightcamera includes a second sensor and second input optics, and wherein thefirst input optics and second input optics transmit respectivewavelength bands of optical radiation that are different from each otherto the corresponding sensors.

5. The binocular system of paragraph 4, wherein the first sensor and thesecond sensor are sensitive to a same wavelength band of opticalradiation.

6. The binocular system of any of paragraphs 2 to 5, wherein the firstwavelength band and the second wavelength band overlap one another.

7. The binocular system of any of paragraphs 1 to 6, wherein each of thecameras is an infrared camera.

8. The binocular system of paragraph 7, wherein one of the camerasdetects short-wave infrared (SWIR) radiation and the other of thecameras detects mid-wave infrared (MWIR) radiation and/or long-waveinfrared (LWIR) radiation.

9. The binocular system of paragraph 7, wherein both of the camerasdetect mid-wave infrared radiation and/or long-wave infrared radiation.

10. The binocular system of paragraph 7, wherein both of the camerasdetect short-wave infrared radiation.

11. The binocular system of any of paragraphs 1 to 4, wherein one of thecameras is a visible light camera and the other of the cameras is aninfrared camera.

12. The binocular system of paragraph 11, wherein the infrared cameradetects short-wave infrared radiation.

13. The binocular system of paragraph 11, wherein the infrared cameradetects mid-wave infrared radiation and/or long-wave infrared radiation.

14. The binocular system of any of paragraphs 1 to 13, wherein one orboth of the cameras includes input optics that include a filter thatfilters optical radiation before such radiation is detected by a camera.

15. The binocular system of paragraph 14, wherein the filter selectivelyblocks only part of the spectrum of infrared radiation.

16. The binocular system of paragraph 15, wherein the filter selectivelyblocks only part of the spectrum of long-wave infrared radiation.

17. The binocular system of paragraph 14, wherein each camera includesone or more filters, and wherein the one or more filters of the leftcamera and of the right camera filter optical radiation differently fromeach other.

18. The binocular system of paragraph 14, wherein each camera includesone or more filters than selectively block only a portion of thespectrum of infrared radiation.

19. The binocular system of paragraph 18, wherein the one or morefilters of each camera selectively block respective wavelength bands oflong-wave infrared radiation that are different from each.

20. The binocular system of paragraph 14, wherein the filter isconfigured to be attached removably to a camera, over an objective lensof such camera.

21. The binocular system of any of paragraphs 1 to 20, furthercomprising a controller programmed to control presentation of left videoimages and right video images by the displays using a different palettefor each display.

22. The binocular system of paragraph 21, wherein one of the palettes isa grayscale palette and the other palette includes one or more colorsthat are not grayscale, and/or wherein a first of the palettes ismonochromatic and a second of the palettes includes at least one colorabsent from the first of the palettes, and/or wherein one of thepalettes is monochromatic and the other palette is polychromatic, orwherein each of the palettes is a grayscale palette and the grayscalepalette for the left display is of inverse polarity from the grayscalepalette for the right display.

23. The binocular system of any of paragraphs 1 to 22, furthercomprising a controller programmed to manipulate one or both videosignals to create a manipulated version of one or both video signals andto drive presentation of video images by one or both displays using themanipulated version.

24. The binocular system of any of paragraphs 1 to 23, wherein thecameras are included in a camera unit and the displays are included in apresentation unit, and wherein the camera unit is movable independentlyof the presentation unit.

25. The binocular system of any of paragraphs 1 to 24, wherein the leftvideo images and the right video images are configured such that aperson viewing such images via the left and right displays can integrateleft images with right images to obtain three-dimensional information.

26. The binocular system of any of paragraphs 1 to 25, wherein arelative intensity of left video images compared to right video imagesis adjustable by a user.

27. The binocular system of paragraph 26, wherein an intensity of leftvideo images presented by the left display and an intensity of rightvideo images presented by the right display are each adjustableindependently of one another by a user.

28. The binocular system of any of paragraphs 1 to 27, furthercomprising a controller and a third camera that creates a third videosignal, wherein the controller is programmed to blend the third videosignal with another of the video signals to produce a blended signal,and wherein a display is configured to present video images based on theblended signal.

29. The binocular system of paragraph 28, wherein the third camerareceives optical radiation along an optical axis that is spaced from theoptical axes along which the left and right cameras receive opticalradiation.

30. The binocular system of any of paragraphs 1 to 29, wherein thedisplays are capable of presenting alphanumeric characters and/or othersymbols with a single display as both displays present video images,such that the characters and/or symbols are seen only with one eye whenthe video images are viewed by a pair of eyes.

31. The binocular system of any of paragraphs 1 to 30, wherein eachdisplay is operatively connected to a respective eyepiece, and wherein afocus of each eyepiece is adjustable independently of the othereyepiece.

32. The binocular system of paragraph 31, wherein a focus of eacheyepiece is adjustable by moving the corresponding display while sucheyepiece remains stationary.

33. The binocular system of any of paragraphs 1 to 32, wherein thedisplays are capable of presenting other information with a singledisplay as both displays present video images, such that the otherinformation is only seen with one eye when the video images are viewedby a pair of eyes.

34. The binocular system of paragraph 33, wherein the other informationincludes one or more alphanumeric characters and/or other symbols.

35. The binocular system of paragraph 33 or 34, wherein the otherinformation at least partially overlaps video images presented by thesingle display.

36. The binocular system of any of paragraphs 33 to 35, wherein theother information and video images are presented at least partiallyadjacent each other by the single display.

37. The binocular system of any of paragraphs 1 to 36, furthercomprising a controller programmed (a) to determine a distance from thesystem to an object represented in the video images based on processingthe left and right video signals, and (b) to drive presentation of anindication of the distance by at least one of the displays.

38. The binocular system of paragraph 37, wherein the controller isprogrammed to cause at least a portion of a representation of the objectin one or more of the video images to be displayed in a color thatindicates the distance.

39. The binocular system of paragraph 37, wherein the controller isprogrammed to indicate the distance as other information that isdisplayed along with the video images.

40. The binocular system of any of paragraphs 1 to 39, furthercomprising a controller and a third camera that creates a third videosignal, wherein the controller is programmed to blend the third videosignal with another of the video signals to produce a blended signal,and wherein a display is configured to present video images based on theblended signal.

41. The binocular system of paragraph 40, wherein the third camerareceives optical radiation along an optical axis that is spaced from theoptical axes along which the left and right cameras receive opticalradiation.

42. The binocular system of paragraph 40, wherein the third camerashares at least part of an optical axis with another of the cameras.

43. The binocular system of any of paragraphs 1 to 42, furthercomprising a controller operatively connected to the displays andprogrammed to drive presentation of left video images and right videoimages formed using a different palette for each display.

44. The binocular system of paragraph 43, wherein the controller isprogrammed to drive presentation of black-and-white video images by oneof the displays and video images including at least one color absentfrom the black-and-white videos by the other display.

45. The binocular system of any of paragraphs 1 to 44, furthercomprising a controller that is operatively connected to the displays,wherein the controller is programmed to drive display of alphanumericcharacters by at least one of the displays, and wherein the controlleris programmed to flip the alphanumeric characters automatically and/orin response to a user input, for presentation of the characters in aright-side up orientation to a user when the binocular system is turnedupside down.

46. The binocular system of any of paragraphs 1 to 45, wherein eachdisplay is operative connected to any eyepiece, further comprising aneye cup connected to each eyepiece and configured to form a substantialseal generally around a user's eye to restrict leakage of light.

47. The binocular system of any of paragraphs 1 to 46, wherein eachcamera includes an objective lens that includes a diamond coating and/ora diamond-like carbon coating on an exterior surface region of theobjective lens.

48. The binocular system of any of paragraphs 1 to 47, furthercomprising a controller programmed to process image data in the videosignals and to control presentation of video images by the displaysbased on the processed image data, wherein the controller is programmedto process the image data to perform facial recognition, scintillationmitigation, nonuniform correction, intent determination, or anycombination thereof.

49. The binocular system of any of paragraphs 1 to 48, furthercomprising a controller programmed to implement an electronic zoom ofpresented video images.

50. The binocular system of paragraph 49, wherein the controller isprogrammed to implement a stepped zoom in response to user input.

51. The binocular system of paragraph 48 or 49, wherein the controlleris programmed to implement a smooth zoom in response to user input.

52. The binocular system of any of paragraphs 1 to 51, furthercomprising a controller operatively connected to the displays andprogrammed to drive presentation of left video images and right videoimages formed using a different palette for each display.

53. The binocular system of paragraph 52, wherein the controller isprogrammed to drive presentation of black-and-white video images by onethe displays and color video images by the other display.

54. The binocular system of paragraph 53, wherein the color video imagesinclude regions that are black and white.

55. The binocular system of paragraph 52, wherein the controller isprogrammed to drive presentation of video images that are at leastsubstantially black and white and have inverse polarity relative to oneanother.

56. The binocular system of any of paragraphs 1 to 55, furthercomprising head-mounting structure configured to permit the binocularsystem to be mounted on a user's head.

57. The binocular system of any of paragraphs 1 to 56, furthercomprising a port configured to permit a dual-channel video signalrepresenting the left and right video signals to be outputted by thebinocular system.

58. The binocular system of any of paragraphs 1 to 29, 31, 32, and 37 to57, further comprising a controller programmed to drive presentation ofalphanumeric characters and/or other symbols with a positional offset inleft video images relative to right video images, thereby causing thecharacters and/or other symbols to be perceived as being disposed at oneor more positions along a depth axis when viewed by a user.

59. The binocular system of any of paragraphs 1 to 58, wherein thesystem is sealed to restrict water entry, to permit submersion in waterwithout damaging the cameras or displays.

60. A method of providing video of a scene, comprising: (A) creatingleft and right video signals from incident optical radiation receivedfrom about a same field of view along left and right optical axes thatare parallel to and offset from one another, the left and right videosignals respectively representing optical radiation detected from afirst wavelength band and a second wavelength band, the first and secondwavelength bands being different from each other and at least one of thewavelength bands including infrared radiation; and (B) presenting leftand right video images formed with visible light based respectively onthe left and right video signals.

61. The method of paragraph 60, further comprising a step of receivingthe left and right video images at respective left and right eyepiecesarranged to be aligned with a pair of eyes.

62. The method of paragraph 60 or 61, wherein the step of creating isperformed with a plurality of sensors, further comprising a step ofplacing a filter in an optical path to a sensor before the step ofdetecting.

63. The method of paragraph 62, wherein the step of placing a filterincludes a step of placing a filter over an objective lens.

64. The method of any of paragraphs 60 to 63, wherein the step ofcreating includes a step of detecting radiation from within a firstwavelength band and a second wavelength band that are both infraredradiation.

65. The method of any of paragraphs 60 to 64, further comprising a stepof presenting other information with one of the displays as bothdisplays present video images, such that the other information is onlyseen with one eye when the video images are viewed by a pair of eyes.

66. A method of providing video of a scene, comprising: (A) detectingoptical radiation received from about a same field of view alongrespective left and right optical axes that are parallel to and offsetfrom one another, to create left and right video signals; (B) drivingpresentation of left and right video images formed with visible lightbased respectively on the left and right video signals; (C) receivingthe left and right video images at respective left and right eyepiecesarranged to be aligned with a left eye and a right eye of a person; and(D) driving presentation of other information by one of the displays asboth displays present video images, such that the other information isonly seen with one eye when the video images are viewed by a pair ofeyes.

67. The method of paragraph 66, wherein the step of driving presentationof other information includes a step of incorporating an overlay intovideo images presented by the one display.

68. The method of paragraph 66 or 67, wherein the step of drivingpresentation of other information includes a step of drivingpresentation of one or more alphanumeric characters and/or othersymbols.

69. A method of observing a scene, comprising: (A) aiming a left cameraand a right camera at a scene to create left and right video signalsfrom detected optical radiation received from about a same field of viewof the scene along respective left and right optical axes that areparallel to and offset from one another, the left camera and the rightcamera being configured to detect optical radiation from respectivefirst and second wavelength bands that are different from one another,at least one of the cameras including a sensor that is sensitive toinfrared radiation; and (B) viewing, with respective left and righteyes, left video images and right video images formed with visible lightbased on the corresponding left and right video signals.

70. The method of paragraph 69, wherein the step of aiming includes astep of aiming a camera unit that includes the left camera and the rightcamera, and wherein the step of viewing includes a step of viewing videoimages provided by a presentation unit that is remote from the cameraunit.

71. The method of paragraph 70, wherein the step of aiming includes astep of moving the camera unit independently of the presentation unit.

72. The method of any of paragraphs 69 to 71, wherein the step ofviewing is performed to identify areas in which soil has been disturbed.

73. The method of paragraph 72, wherein the soil has a Restrahlen band,and wherein only one of the cameras is configured to detect opticalradiation substantially in the Restrahlen band.

74. The method of paragraph 69, wherein the step of viewing is performedto identify sites of gas emission and/or gas leakage for a gas ofinterest.

75. The method of paragraph 74, wherein the gas of interest has anabsorption band, and wherein only one of the cameras is configured todetect optical radiation substantially in the absorption band.

The disclosure set forth above may encompass multiple distinctinventions with independent utility. Although each of these inventionshas been disclosed in its preferred form(s), the specific embodimentsthereof as disclosed and illustrated herein are not to be considered ina limiting sense, because numerous variations are possible. The subjectmatter of the inventions includes all novel and nonobvious combinationsand subcombinations of the various elements, features, functions, and/orproperties disclosed herein. The following claims particularly point outcertain combinations and subcombinations regarded as novel andnonobvious. Inventions embodied in other combinations andsubcombinations of features, functions, elements, and/or properties maybe claimed in applications claiming priority from this or a relatedapplication. Such claims, whether directed to a different invention orto the same invention, and whether broader, narrower, equal, ordifferent in scope to the original claims, also are regarded as includedwithin the subject matter of the inventions of the present disclosure.

1. A binocular system, comprising: a left camera and a right camera thatcreate left and right video signals from detected optical radiationreceived from about a same field of view along respective left and rightoptical axes that are parallel to and offset from each other, at leastone of the cameras including a sensor that is sensitive to infraredradiation; and a left display and a right display arranged to be viewedby a pair of eyes and configured to present left and right video imagesformed with visible light based respectively on the left and right videosignals, wherein each display is operatively connected to a respectiveeyepiece, and wherein a focus of each eyepiece is adjustableindependently of the other eyepiece.
 2. The binocular system of claim 1,further comprising an eye cup connected to each eyepiece and configuredto form a substantial seal generally around a user's eye to restrictleakage of light.
 3. The binocular system of claim 1, wherein eachcamera includes an objective lens that includes a diamond coating and/ora diamond-like carbon coating on an exterior surface region of theobjective lens.
 4. The binocular system of claim 1, wherein the displaysare capable of presenting alphanumeric characters and/or other symbolswith a single display as both displays present video images, such thatthe other information is only seen with one eye when the video imagesare viewed by a pair of eyes.
 5. The binocular system of claim 4,wherein the alphanumeric characters are automatically flipped forpresentation in a right-side up orientation to a user when the binocularsystem is turned upside down.
 6. The binocular system of claim 1,further comprising a controller programmed to process image data in thevideo signals and to control presentation of video images by thedisplays based on the processed image data, wherein the controller isprogrammed to process the image data to perform facial recognition,scintillation mitigation, nonuniform correction, intent determination,or any combination thereof.
 7. The binocular system of claim 1, furthercomprising a controller programmed to implement an electronic zoom ofpresented video images.
 8. The binocular system of claim 7, wherein thecontroller is programmed to implement a stepped zoom in response to userinput.
 9. The binocular system of claim 7, wherein the controller isprogrammed to implement a smooth zoom in response to user input.
 10. Thebinocular system of claim 1, wherein a relative intensity of left videoimages compared to right video images is adjustable by a user.
 11. Thebinocular system of claim 1, further comprising a controller operativelyconnected to the displays and programmed to drive presentation of leftvideo images and right video images formed using a different palette foreach display.
 12. The binocular system of claim 11, wherein thecontroller is programmed to drive presentation of monochromatic videoimages by one the displays and video images including one or more colorsabsent from the monochromatic video images by the other display.
 13. Thebinocular system of claim 12, wherein the video images including one ormore colors are substantially monochromatic.
 14. The binocular system ofclaim 11, wherein the controller is programmed to color-code regions invideo images presented by one of the displays while the other displaypresents video images that are not color-coded.
 15. The binocular systemof claim 11, wherein the controller is programmed to drive presentationof monochromatic video images having inverse polarity relative to oneanother.
 16. The binocular system of claim 1, further comprisinghead-mounting structure configured to permit the binocular system to bemounted on a user's head.
 17. The binocular system of claim 1, furthercomprising a communication port configured to permit a dual-channelvideo signal representing the left and right video signals to beoutputted by the binocular system.
 18. The binocular system of claim 1,further comprising a controller programmed (a) to determine a distancefrom the system to an object represented in the video images based onprocessing the left and right video signals, and (b) to drivepresentation by at least one of the displays of an indication of thedistance.
 19. The binocular system of claim 1, further comprising acontroller programmed to drive presentation of alphanumeric charactersand/or other symbols with a positional offset in left video imagesrelative to right video images.
 20. The binocular system of claim 1,wherein the system is sealed to restrict water entry, to permitsubmersion in water without damaging the cameras or displays. 21.-46.(canceled)